A British riot police officer has been acquitted of any wrongdoing regarding the death of a newspaper vendor during last year's G20 protests.

The policeman had been filmed pushing Ian Tomlinson to the ground during the G20 riots after he was hit by a baton and shoved to the ground.

Tomlinson was seen in mobile phone footage moving away after the incident but collapsed 100 meters away in Cornhill.

Police claimed that he had died of a heart attack, a claim supported by an initial post mortem, but second and third post mortems concluded that Tomlinson died from abdominal hemorrhage.

After a 15-month inquiry, director of Public Prosecutions Keir Starmer said, "There is no realistic prospect of a conviction."

The ruling means that the riot police officer will not face any charges over the death of the newspaper vendor.

Starmer said there was evidence that the officer, a member of the Metropolitan Police's territorial support group, assaulted Tomlinson, but a manslaughter charge could not be brought because of "irreconcilable" differences between doctors over what caused his death.

He said the evidence of Dr Freddy Patel, who found Tomlinson died of natural causes, could undermine any prosecution.

Tomlinson family solicitor Jules Carey described the ruling as "disgraceful".

Speaking outside the Crown Prosecution Service headquarters, he said the family would consider whether they can appeal against the decision.

"Clearly it is a disgraceful decision. The CPS [Crown Prosecution Service] have accepted the conduct of the officer was unlawful."

"We now need to find out if there has been a lack of will or incompetence, and frankly there needs to be an inquiry into that.

"We will be looking at whether the decision can be reviewed, but that is a matter for another day."

Tomlinson's son Paul King said the family was stunned by the decision.

"It's taken 16 months to get a no-charge against this officer. The CPS have clearly admitted that the police officer assaulted our dad," he said.

"Why hasn't there been a charge? We have to go home to no dad. It has aged us, the wait."